Gauging means for buffing machine



5 Jan. 11, 1966 E. w. ROBERTSON 3,228,110

GAUGING MEANS FOR BUFFING MACHINE Original Filed Sept. 14, 1959 4Sheets-Sheet 1 F/GL/ 55 6 57 5s 78 53 5! 69 52 so I2 H 60 INVENTOR.

ELMER WESLEY ROBERTSON g/wm df Jan. 11, 1966 E. w. ROBERTSON 3,228,110

GAUGING MEANS FOR BUFFING MACHINE Original Filed Sept. 14, 1959 4Sheets-Sheet 2 FIG. 2

25 93 U F/6 9 QO 96 INVENTOR.

V ELMER WESLEY ROBERTSCW 92 A BY f 98 97 Q6 M L l f 94 HIS ATTORNEYSJan. 11, 1966 E. w. ROBERTSON GAUGING MEANS FOR BUFFING MACHINE 4Sheets-Sheet 5 Original Filed Sept. 14, 1959 INVENTOR. 62MB? WSLVROBHTSGN vlvllllllll llllllll 7;

7 EIIIIII [Il'll illlll H/S A T TORNEVS 11, 1956 E. w. ROBERTSON3,223,110

GAUGING MEANS FOR BUFFING MACHINE Original Filed Sept. 14, 1959 4Sheets-Sheet 4.

F/GJO 65 72 Z2 Z3 24 25 Z6 Z7 2 INVEN TOR. ELMER WESLEY ROBERT SQV BY WH/S ATTOPMF VS United States Patent Ofiice 3,228,110 GAUGING MEANS FORBUFFH'JG MACHINE Elmer Wesley Robertson, Berkeley, Calif., assignor, byInesne assignments, to Elriek Industries, Inc., Oakland, Calif.

Griginal application Sept. 14, 1959, Ser. No. 839,796, now Patent No.3,080,899, dated Mar. 12, 1963. Divided and this application Jan. 14,1963, Ser. No. 251,215

7 Claims. (Cl. 33174) This invention relates to tire buffing equipmentand more particularly to a tire mount, support and gauging means forprecision buffing of rubber tires.

The art of tire buffing is replete with articulatable means forsupporting tire carcases adjacent a motor driven buffing drum fortangent engagement therewith to remove tread rubber from the tirepreparatory to vulcanization of recap rubber onto the periphery of thetire body.

While these prior known tire butting machines have been thoughtsatisfactory, they leave much to be desired by reason of irregularbuffing; their failure to properly gauge the diameter, crown contourand/ or crown width of the 'bufifed tire. In many of the prior devicesthe tire carcase is buffed out of round resulting in either had curingof the recap rubber due to too thick or too thin a layer of recapmaterial. For example, in recapping tires, the bulfed carcase is placedin a matrix or mold with recap rubber or camel back" applied to theperiphery of the tire. The matrix is accurately diametered but if thebuffed tire body is out of round or the buffed surface irregular therewill be a variance in spacing between the irregular Zones of the tirebody and the matrix walls. This results in thin spots wherein the recaprubber is compressed too much so as to become hardened and thereforebadly cured. Contrariwise if the space between the buifed tire andmatrix is greater than required the recap rubber may become spongyand/or soft. In either case the wear of such hard and/or soft zones ofrecap rubber become excessive during use resulting in less than thequality job expected by the tire owner or user.

The present invention contemplates the provision in tire bufiingequipment of means facilitating, during buffing, the attainment of atrue round, a proper diameter, a correct crown contour and crown widthas well as a low shoulder upon the buffed tire body so as to assure acomplete and uniform covering and curing of the recap rubber appliedthereto.

The present invention is shown associated with one particular form oftire mount of the type shown, described and claimed in United StateLetters Patent No. 3,080,899 which issued March 12, 1963 from mycpending application Serial No. 839,706, filed September 14, 1959 and isa divisional application of the same.

In connection with the tire mount shown in the present application it isanother object to provide means for inflating the tire mounted thereonto a limited pressure such a to bring it into a shape or form comparableto its natural state while mounted on the wheel of a vehicle. In thismanner the tire is brought into shape for firm engagement with thebufiing wheel or drum as well as the gauging means of the presentinvention.

The present invention also include means for indieating the depth of cutor removal of old tread rubber from the tire during bufiing. By thisarrangement there is provided means for gauging the diameter of thebulfed tire and incidental thereto attaining true round of the peripheryof the bufied tire preparatory to the application of recap rubberthereto. In this manner the proper thickness and curing of recap rubberto such true round 3,228,110 Patented Jan. 11, 1966 buffed tire withrespect to the vulcanizing matrix or mold is assured.

This attainment of proper curing and application of recap rubber to theperiphery of a tire casing further entails a gauging or determination ofbuffed crown contour or radius, buffed crown width and a preparation ofthe shoulder of the tire to a proper shape for feathering out the recaprubber from the crown down to the scuif bar thereof. To this end thereis provided a preset gauge adapted to engage the periphery of the tireduring buffing thereof whereby the person operating the butter candetect when the tire has been buffed to the proper diameter, is true ofround, has the proper crown contour and width.

These, and other objects and advantages of the present invention willbecome apparent from a reading of the following description .inconnection with the drawings in which:

FIG. 1 is a perspective view of a tire buffing arbor having the tiresupport and gauging means of the present invention embodied therein.

FIG. 2 is an elevational view of the tire support of the presentinvention with a tire supported therein.

FIG. 3 is a side view of FIG. 2.

FIG. 4 i an enlarged fragmentary section through the periphery and webof one of the half rims.

FIG. 5 is an enlarged elevational View of the gauging means of FIG. 2.

FIG. 6 is a side view of FIG. 5 which is an enlarged etail of the gaugemeans seen in FIG. 3.

FIG. 7 is a section through FIG. 5 taken along line 77 thereof to show aturret mount for the gauging rollers.

FIG. 8 is a ection through FIG. 6.

FIG. 9 is a fragmentary elevation of part of FIG. 4.

FIG. 10 is a partial section of the assembly showing modified form ofgauging means.

FIG. 11 is a section through FIG. 10 taken along line 11-11 of FIG. 10.

General In general the present invention is embodied in a tire bufiingarrangement of the type in which a tire to be buffed is supported forrotation on horizontal spindles journaled in a support swingable in ahorizontal plane whereby the periphery of the tire is presented fortangent engagement with a power driven buffing drum supported on anadjacent arbor.

More specifically, referring to FIG. 1, the overall arrangement isassociated with a boiling drum 10 disposed for rotation on a horizontalarbor 11 powered by a motor 12 and supported on a tandard 13. The tiremount embodying the present invention, generally designated 15, issupported adjacent the arbor 11 in the usual manner so as to present theperiphery of a tire to be buffed for tangent engagement with the raspingface of the bufling drum 10.

Tire support The support 16 for the tire mount 15 consists of a pedestal17 having a pair of pivoted arms 18 and 19 pivotally mounted thereon forswinging movement in a horizontal plane. A tire supporting frame in theform of a fork-like yoke 20 has a vertical pin 21 at its bight pivotallymounted at the end of the outermost arm 19 so that the yoke can berocked about horizontally relative to the dual swing arms 18 and 19. Inthis manner the yoke 20 provides a pair of upright legs 22 and 22'between which to support a tire T. The tire T is adapted to be supportedon a pair of disc wheels providing split rims 25 and 25' each mounted ona half spindle 2646', respectively, each journaled midway up arespective one of the upstanding legs 22 and 22 of the yoke 20. To this3 end each leg 22 and 22 is provided with a boss 27-27 housing a rollerbearing 28-28 and having thrust bearings 29-29 (FIG. 10) on their innersides against which a collar 30-30 on the half spindles 26-26respectively bears.

The outer and of half spindle 26 is keyed to and coaxially of a driveshaft drivingly connected to a motor M. In the disclosure of FIGS. 1, 2and 3 the motor M has its housing secured to the arm 22 flush withoutside face of the boss 27 thereon. The outer end of the other halfspindle 26 is threaded to receive a nut N which bears against the outerface of the boss 27 on the arm 22. The inner end of half spindle 26 hasan axial bore 31 adapted to rceive a reduced, beveled end 31 of theother half spindle 26 when the yoke 20 is in closed condition.

The two half or split rims 25 and 25 are identical and interchangeableand for this reason are releasably mounted on the respective halfspindle 26 and 26. This is important from the standpoint of adapting thetire support for tires of larger and/or smaller diameter.

As best seen in FIGS. 2 and 10 spreader type collars 32-32 are providedon each half spindle for adjusting the width of rim to suit tires ofvarious widths. These spreader collars bear against the collar 30-30,respectively, on the half spindles 26-26 and form the base against whichthe small convolute of a spiral spring 33-33 bears. The opposite orlarger convolute of the spring 33-33 bears against a flanged end 34-34of a hub 35-35 mounted on the respective half spindle 26-26 and adaptedto receive the respective rim half 25 and 25. The hub 35 is keyed to itsspindle shaft 26-26 as seen in FIG. 10 and each hub 35-35 is pressedagainst the spiral spring 33-33 and secured longitudinally of thespindle 26-26 and against removal therefrom under the influence of thespiral spring by a neoprene washer or O ring -0.

Replaceable rims and rim diameter Each split rim 25 and 25 by the sametoken is secured to the hub 35 and 35, respectively, by a snap ring36-36 which seats in an annular groove formed adjacent the inner end ofthe particular hub 35-35 with which it is associated. Each flange 34-34has inwardly extending pins P-P radially arranged thereon about the hub35-35 so as to extend into bores provided in web-like spokes 37-37 ofthe respective split half of the rim 25-25 for turning the same with thehub. Since the hub 35 is keyed to the half spindle shaft 26 which isdrivingly connected to the motor M it will be appreciated that when atire T is mounted on the split rims 25-25 to couple them boh of thesplit rims, their hubs and spindle shafts will turn in unison.

The split rims 25-25 each have a tire bead engaging flange 38-38 formaintaining the tire in engagement therewith and as will be noted inFIG. each rim half 25-25 has a serrated inner face 39-39" such thatalthough these faces engage each other, air can pass from the spacebetween the rims into the cavity of the tire body. In this connectionnote that one of the half spindles 26 has a center bore 40 communicatingwith an air supply conduit 41 in turn communicating with a source ofconstant air supply (not shown). The air supply conduit 41 has an airregulator 42 in line with it to limit the air supply to a predeterminedadmittance valve. Note also that each of the rim halves 25-25 is formedon a solid disc so that air passing through the bore 40, and escapingtherefrom via ports 43 into the space between the discs and rims 25-25,flows into the cavity of the tire T to in flate it even during rotation.

Safety valve In providing a source of constant air supply under pressureto the space between the discs and rims 25-25 to inflate the tirethereon it has been found that a pressure beyond an allowable limitshould be avoided to assure against accidental over inflation of thetire. A

pressure of 5 pounds per square inch is sufficient to brace the tire forbufling and any pressure beyond 12 pounds per square inch may undulystrain the seal between the tire beads and half rims or put an unduestress on the tire supporting frame. For these reasons it is desirablethat a safety blow out plug or some form of relief valve be provided toassure against excess pressures building up within the tire and spacebetween the discs of the rim halves 25-25. Such a relief valve is shownat in FIG. 4. The construction consists of a cap 91 mounted for sealedsliding movement on an outwardly extending stem 92 threaded to the discwheel. The cap 91 has a sealing washer or ring 93 embedded therein toengage the outside wall of the disc 94 around a plurality of ports orapertures 96 formed in the disc 94. The outer end of the stem 92 isthreaded and has a compression spring 97 thereon engaged by a nut 98 onthe outer end of the stem. By this arrangement pressures built upbetween the two disc wheels bears against the full surface of cap 91 viathe ports 96 to force the cap 91 and washer 93 away from the disc 94 tothereby relieve pressure within the tire cavity and between the spacedrims and discs. The spring 97 is calculated to yield at the desiredpressure (5 pounds) and the plural ports 96 are of a combined area tocounteract the load of the spring 97 so as to assure relief of pressureand to maintain a seal during drop in pressure.

Step-up rings The foregoing arrangement is suited within limits forreceiving and supporting tires of various rim diameter as Well asvarious rim width. For example the split rims 25-25 of themselves arediametered to receive, say, a tire rim of 15 inch diameter. Each rimhalf has a flange 38-38 against which the head of the tire T can engage.Should it be required that a tire of 16 inch diameter be placed on.these rims 25-25, I have provided step-up rings, each adapted to havestretch fit with a rim 25 or 25' one 44 of which step-up ring isillustrated in section in FIG. 4.

Each step-up ring 44-44 is identical and presents a bead flange 45adapted to conform to the head of the next larger tire to be received.There may be another step-up ring placed over the steep-up rim 44 or 44to suit the split rims to receive the next larger diametered tire.

Spreader collars-compensation for tire widths Tire also vary in width,i.e., the distance between rim beads thereof may be wide or narrow. Forexample, tires may be divided into three groups so far as width of rimis concerned, namely, group A 5.90 to 6.70, group B 7.10 to 8.00 andgroup C 8.50 to 9.50, these measurements being the size in inches of thecross section of the tire cavity. To compensate for such variations inthe width of tires, the spreader collars 32-32 are such as to enable thesplit rims 25-25 to slide outwardly from vertical center of the yoke agreater or lesser distance. To this end each set of collars 32-32consists of a pair of collars having their abutting faces 46 segmentallynotched to provide stepped planar recesses at three different levels ofabutment between them. As illustrated in FIG. 1 the abutting faces ofeach spreader collar are divided into six segmental areas in whichdiametrically opposite areas, a, b and c (FIG. 10) are paired off anddisposed at different planes or depths of recess relative to the outerfaces of the collar members 32 or 32. The segments are interfitting sothat the areas a, b, and c are disposed for interchangeable abuttingrelation with respect to each other so as to coordinately compensate forthe various width groups A, B and C of tire diameter.

For example, when a tire of narrow rim width group A (5.90 to 6.70) isto be mounted on the split rims 25-25, each set of spreader collars hasone half collar disposed with its segmental zones a in engagement withthe zone a of the other mating half collar, as illustrated in FIG. 2. Inthis manner each set of spreader collars is longest,

longitudinally of the half spindle shaft 26 or 26' upon which it ismounted so that the half rims -25 are limited to the least spreadingrelative to each other. However, if the tire to be mounted on the splitrims is of greater width, say in the next width group B of 7.10 to 8.00,one half collar is turned 60 degrees relative to its mating half collarso that the segmental zone a of one half collar is in abutting relationto the zone b of its mating half collar. This would allow the half rims25-25 to spread relative to each other partially but not fully. By thesame token if a tire of the wider group C (8.50 to 9.50) were to bemounted on the split rims 25-25 the spreader collars 32-32 would havetheir mating halves disposed such that the zones (1 of one half wouldabut the zones 0 of the other or mating half collar as illustrated inFIG. 10. Thus the spreader collars 32-32 are set for their shortestlength and allow the half rims 25-25 to spread the greatest distancerelative to each other to accommodate the wider group of tires.

In connection with the foregoing it should be borne in mind that thespiral spring 33-33 is interposed between the spreader collar 32-32 andthe rim half 25-25, respectively, when the deflated or relaxed tire bodyis mounted on the split rims. However these spiral springs will yieldwhen pressure builds up in the tire to cause the tire to spread the rimhalves until the spiral springs are fully compressed, i.e., flattenedout, between the hub 35-35 and the collar 32-32 which limits outwardmovement of the split rims.

By the same token these spiral springs 33-33 bear with considerablepressure against the innermost one of each pair of spreader collars32-32 so as to maintain each pair of collars in abutting relationregardless of which segmental area a, b or c of one half collar abutswhatever segmental area a, b or c of the other. Note (FIG. 2) that oneof the half collars has diametrical finger tabs F by which to compressthe spring 33 or 33 as well as to facilitate turning s-uch half collarrelative to the other during adjustment.

At all events it will be appreciated that all tires, regardless ofvariations in width, are mounted on the split rims in accurate verticalcenter of the yoke 20, i.e. the pivot pin 21 thereof.

Openable yoke Having thus described the nature and construction of thetire mounting spindle and wheel I shall now explain the support yoke 20therefor in details more pertinent to the present invention. ContrastingFIG. 1 with FIG. 2 it will be noted that the support yoke 20 of thepresent invention is openable to receive a tire to be mounted on thewheel made up of the split rims. In combination therewith I haveprovided means 43 for releasably latching the openable arms 22-22' ofthe yoke in closed condition.

To accomplish the openability of the yoke one arm 22 thereof ispivotally mounted as at 49 for movement relative to the other arm 22 atthe bignt of the yoke, i.e., adjacent the vertical pin 21 by which theyoke is mounted upon the dual arms 18-19 for horizontal swinging. Itwill thus be appreciated that the arm 22 is movable while the other arm22 is stationary although both are swingable as a unit or common yoke.

The latch means 48 is at the upper or opposite ends of the yoke arms22-22' for binding them together in spaced parallel relation. To thisend the stationary arm 22' has a bridge piece or cross brace 50 formedintegrally therewith so as to extend laterally therefrom to present oneend 51 thereof for abutting relation with the free end 52 of the otheror movable arm 22. The cross brace 50 has a flat flange 53 on its end 51which is slotted to receive a vertical fiange 54 formed on the free ned52 of the movable arm 22 to align the yoke arms with each other. A latcharm 55 pivotally mounted at 57 between parallel linkages 56 which inturn have their opposite ends embracing the end cross brace 50 pivotallyconnected as at 58 to the end 51 of the brace 50. In this manner thespaced linkages 56 are swingable over the free end 52 of the movable arm22 to position the latch arm 55 for engagement therewith.

The latch arm 55 has a cam formation 59 eccentric of its point ofpivotation 57 adapted to engage in a recess 60 formed on the edge of theupper free end 52 of the movable arm 22. The arrangement is such thatwhen the latch arm 55 is turned upward the linkages 56 and cam 59 canpass over the upper end 52 of arm 22 and when latch arm 55 is swung byhand downwardly its eccentric cam 59 engages in the recessed edge 60 ofarm 22 to bind ingly latch the movable arm 22 against the cross bridge5i) of the yoke.

From the foregoing it will be appreciated that a tire T is easilymounted on the split rims 25-25 which are carried by the respective arms22-22 of the yoke. The workman need merely open up the yoke, place thetire on one rim half and close the yoke and latch the arms together.Thus it will be seen that the tire is completely encompassed by theclosed yoke which moves as a unit about its vertical mounting pin 21 topresent the periphery of the tire to the butfing drum it).

Suitable handles H on each arm 22-22 (FIGS. 1, 2 and 3) serve for thegrasp and guidance by the hands of the person operating the buffer.

In conjunction with the openability of the yoke 20 it should be notedthat I have provided a cushioning means 61 to alleviate shock to thepivotal connection between the yoke arms when the latch 55 is opened andthe movable arm 22 allowed to drop away into open position. As seen inFIGS. 1, 2 and 3 the cushioning means 61 may consist of an extension 62on movable arm 22 and a compression spring 63 between the end of theextension 62 and the adjacent stationary arm 22 of the yoke. Thearrangement is such that when the movable arm 22 swings away from thestationary arm 22, the compression spring 63 serves to take up themomentum of such movement.

Tire gauging The tire gauging means which forms the subject of thepresent invention embodies a preset gauge 65 including a templatedisposed on a turret 66 to selectively engage the tire T so as tovisually aid the operator in deter mining when buffing is complete.

Referring to FIGS. 5 and 7 the turret 66 carries a plurality of rollers67 each a template for reasons later to be explained. Sufiice it at thispoint to say that a roller 67 mounted for rotation on a shaft 68 whichextends parallel to the spindle shafts 26-26 above the tire T so as tomove by gravity radially toward the latter. The shaft 68 is carried by arider 69 guided for up and down movement in a track 70 provided on onearm of the yoke, preferably the stationary arm 22 thereof. The track 70consists of a vertical slot formed through the arm 22 in a planeparallel to the spindles 26-26. The rider 69 consists of a blockslidably arranged in the slot 70 and having upper and lower frustoconical rollers 69 disposed to engage beveled edges 70 formed on the arm22 at each side of the slot 70 to keep the block in alignment with theslot. It will be noted that the roller 67 gravitates toward theperiphery of the tire T to be bufled.

The present invention embodies means 71 for limiting gravitationalmovement of the template roller 67 toward the periphery of the tire soas to indicate to the operator that the bufiing operation is complete.The limiting means 71 embodies the aforementioned preset gauge 65 whichincludes a full scale rule 72 mounted on top of the cross bridge 50 anda pointer 73 movable relative to the scale 72 and connected by flexiblecable 74 to the rider 69 so as to coordinate the movement of the latterand the roller 67 with movement of the pointer 73 along the scale 72. Asbest seen in FIGS. 5 and 6 the roller 67 moves radially toward theperiphery of a tire to reflect radial distance whereas the pointer 73moves twice the distance of movement of the roller so as to aiford afull scale reading of the tire diameter rather than tire radius. This isaccomplished by supporting the rider 69 in a loop 75 of the cable 74rather than having one end of the cable connected directly to the rider69.

Referring to FIGS. and 6 it will be seen that the pointer 73 is formedas a part of a rider which rides in a slot 76 formed lengthwise of thescale 72. A knurled thumb nut 77 associated with the rider has threadedconnection with a clamp jaw 77' on the back side of the scale 72 bywhich to secure the rider and its pointer 73 at any desired diameterreading along the scale when the thumb nut 77 draws clamp jaw 77' upagainst the scale. One end of the cable 74 is secured to the pointer andthe cable extends from the pointer parallel to the scale and beyond thearm 22' of the yoke. The cable 74 is trained over a pulley 78 so as tobe directed downward therefrom parallel to the vertically disposed arm22'. The loop 75 of the cable 74 is formed in the region of the track 70 in which the rider 69 is guided for up and down movementand theopposite end of the cable 74 is anchored to an extension X just abovethe track 7 t). A sheave 79 is mounted for rotation on a stud shaft 68'secured to and extending horizontally from the rider 69 exteriorly ofthe yoke 20. The sheave 7? hangs in the loop 75 so that the rider 69 androller 67 is suspended from the cable 74 to limit movement of thetemplate toward the tire being buffed. How ever so long as the tread onthe tire T is unbufled to a diameter corresponding to the presetdiameter reading on the scale as indicated by the pointer 73, the roller67 bears against the periphery of the tire and is not suspended from orsupported by the cable. It is only when the boiling of the tread rubberhas worn the tread rubber down to the diameter desired thatgravitational movement of the roller and rider is limited by reason ofthe sheave 79 hanging on the loop 75 of the cable 74 which is anchoredto the preset pointer 73. Rotation of the roller 67 therefore ceases andthis indicates that buffing of the tire is complete so far as properdiameter is concerned.

Incidental to indicating that buffing to the desired depth has beenattained, since gravitational movement of the roller 67 radially towardthe tire is stopped, the operator is also visually apprised as towhether or not the periphery of the tire has been buffed to a trueround. The suspended roller 67 being at a fixed dimension radially fromthe spindles 26-26 it will be appreciated that if the tire is out ofround, any high zone on the periphery of the tire will obviously engagethe roller 67 and so indicate the out of round.

An alternate form of preset gauge is shown in FIGS. 10

and 11 in which the cable 74 has one end anchored as at X to the frameor yoke above the track 70 formed in the arm 22' thereof. The cable 74extends downwardly and around a sheave 79' formed on the upper outer setof frusto conical rollers 69" which engage the beveled edge 70' of theguide track 70. Thus the loop 75 in cable 74 forms a support for therider 69 and turret 66 carried thereby as before. The cable 74 extendsupwardly from the loop 75 around a pulley 78 and then transverselyacross the top of the bridge brace 50 beneath the scale 72. In thismodification the cable although secured to the pointer 73 continues onaround a pulley 8t) journaled above the free end 51 of the bridge brace50. Thence the cable 74 extends from the lower side of pulley 80 back tothe upper side of a pulley 78' adjacent pulley '78 and thence down to ananchorage Y on the side of the frame below the track 70 formed in thearm 22' thereof.

In this arrangement it will be appreciated that when the pointer ismoved along the scale the loop 75 will be lowered one half the distanceof movement made by the pointer. Now while the pointer might well havemeans thereon such as the nut 77 in FIGS. 5 and 6 for securing it to thescale 72, in this arrangement the scale has a separate rider 81, asecuring nut 77' ahead of the pointer 73 and for limiting movement ofthe pointer toward lesser dimensional readings. In this manner movementof the cable is limited as before and the draped loop 75 disposed tohold the rider 69 suspended to thereby limit further movement of thegauge roller 67 radially toward the tire being bufied.

Crown contour gauge It will be noted in FIGS. 1, 2, 5 and 10 that theroller 67 is not a straight sided cylinder but rather is arcuately cutto provide a template matching the desired crown contour to which thetire is to be buffed. The roller 67 is therefore cut arcuately on aradius disposed along the vertical axis of the fork-like yoke 20', i.e.the plane in which the tire T rotates. It will be appreciated that theradius on which the side wall of the roller is cut will depend upon thewidth of tire to be buffed. There being three groups of tire width, aspreviously explained, I have provided three different template rollersadapted for use in gauging the crown contour of tires of the respectivewidth groups. These three different templates or rollers are designated67a, 67b and 67c, respectively, coordinated with the three groups oftire widths (A, B and C) as hereinbefore referred to.

The arcuate cut of the template roller 67:: is, for example, struckabout a six inch radius; that of the template roller 67b on a seven anda half inch radius; and the arcuate cut of roller 670 is struck from anine inch radius. These three template rollers 67a, 67b and 670 arejournaled on independent shafts 68a, 68b and 630, respectively, (FIGS. 5and 7) each extending from the turrent mounting 66 at triangularlydisposed centers thereof, the turret mounting 66 in turn being mountedon the central shaft 68 secured to the rider 69 as previously explained.

The turret mounting 66 includes a fixed plate 82 welded to a sleeve 83which is secured to the rider 69 concentric to the shaft 68. The shafts68a, 68b and 680 for each template roller 67a, 67 b and 67c,respectively, is mounted on end plates 8484 each rotatably mounted onthe central shaft 68 for rotation relative thereto. A spring urged pin85 carried by the fixed plate 82 is disposed to enter one or another ofthe recesses 84a, 84b or 84c formed on the end plate which is adjacentthe fixed plate 82 to thereby secure the turret mount for the templaterollers relative to the fixed plate 82. In this manner, any one of thetemplate rollers 67a, 67b or 670 can be selectively positioned to engagethe periphery of the tire T to be buifed.

Referring again to FIGS. 2 and 5 as well as FIG. 10 it will be notedthat each of the template rollers 67a, 67b and 67c has thereon pairedscribe lines 86-86. Each of the pairs of these scribe lines 8686 areequidistant from the vertical axis of the yoke 20 as well as the axis ofthe plane in which the tire is supported therein to rotate. The purposeof these scribe lines 86-86 is to set up visual sight lines duringrotation of the roller 67 engaging the tire being buffed to indicate, tothe operator, the crown width for the particular tire being buffed.

The crown Width is that width of the arcuately buffed periphery which ismost suitable for receiving recap rubber and entails the bufiing of theshoulders S on each side of the tire between the crown and scuff bar onthe side wall of the tire. In other words, after the operator has bufredthe crown of the tire to the proper diameter as indicated by suspensionof the turret rollers 67 from the cable 74 dependent upon the pointerpresetting relative to the scale; and has bufied the crown to the propercontour as indicated by the matching thereof with the template roller;he turns the yoke 20 either way to a sidewise cant relative to thebufiing drum 10 so as to butt the shoulders S. In boiling the shouldersS the operator matches the corner between the crown and shoulder withthe particular scribe line 86 or 86 designating the proper crown widthfor the particular size of tire being buffed. In this manner the tirecan be accurately buffed to receive the recap rubber with assurance thatit will be of uniform thickness and application when the same is moldedand vulcanized in the matrix.

In summary the foregoing structure is utilized as follows: The tire tobe buffed is checked for size and the bufiing machine adjusted foroperation on that particular tire.

First if the half rims 25-25 are not suited for the particular tire tobe buffed even with a step-up ring thereon, the half discs are changedby pulling off the snap rings 36-36 and sliding the disc wheels off totheir hubs and pins P-P for replacement by suitably sized half discwheels.

Next the spreader collars 32-32 are set to limit outward movement of thehalf disc wheels under the influence of pressurized air therebetween,the setting of the spreader collars being dependent upon the width ofthe particular tire to be bufi'ed.

The tire is then hung over the half rim 25 and movable arm 22 swung upinto closed condition and the latch means 48 secured. Now air pressureis admited via passage 41 in spindle 26 and constantly flows into thespace between the half discs, the pressure building up within the tirebeing set at, say pounds on the safety relief valve 96.

Next the preset gauge 65 is checked to set its pointer 73 in line withthe desired tire diameter reading corresponding to the depth of bufiingrequired on the particular tire to be buffed. At this time or justbefore the turret on the rider 69 is checked to present the propertemplate roller 67 to the particular tire to be buffed. The templateroller selected will then gravitate 'into engagement with the peripheryof the tire to be buffed.

The operator now turns on the power to the motor M so as to turn thetire in a direction contra to the direction of rotation of the bufiingdrum 1t He now grasps the handles H on the fork-like yoke 20 so as tocontrol the horizontal swing thereof and to force the periphery towardthe bufiing drum for tangent engagement therewith. As the tread rubberis thus worn away from the tire the operator matches the crown countourof the tire with the arcuate surface of the template roller 67. When thetread rubber reaches a depth such that the rider 69 becomes suspended onthe draped section 75 of the cable 74 any further bufl'ing would cause adisengagement of the template roller 67 with the tire. Accordinglyfurther bufiing of the crown is stopped and buffing of the shoulders atthe sides of the crown begin. In buifing the shoulders the operatorvisually aligns the point of convergence of the crown and shoulder witha scribe line 86 on the template roller 67 corresponding to the width ofcrown most suitable for the particular tire being buffed. It will herebe noted that although the scribe lines 86-86 extend only segmentallyabout the roller 67, when the roller rotates by reason of contact withthe rotating tire, these scribe lines achieve the allusion of a clearcut reference line by which to guide the operator in buffing theshoulders to the proper crown Width.

Having thus described the new and improved tire buffing machineembodying the present invention it will be appreciated by those skilledin the art that the same is susceptible to variations, alterations and/or modifications without departing from the spirit of my invention. Itherefore desire to avail myself of all variations, alterations and/ormodifications as fairly come within the purview of the appended claims.

What I claim as new and desire to protect by Letters Patent is:

1. In a tire buffing machine in which a tire is supported on a powerdn'ven spindle for rotating such tire while presenting the sametangently to a rotary buffing drum for removing tread rubber from suchtire; preset means for indicating the depth of cut taken into the treadrubber of said tire during bufling thereof by said bufling drumcomprising a tire engaging roller arranged for up and down movementradially from and by gravitation toward said spindle whereby said tireengaging roller rests upon said tire for turning thereby during bufiingthereof, and means for limiting movement of said tire engaging roller bygravitation beyond a predetermined radial distance toward said spindlewhereby said tire engaging roller ceases to rest upon said the and to beturned thereby for indicating visually that said tire has been buffed.to the desired depth.

2. In a tire bufling machine in which a horizontally articulatableopenable fork-like yoke having a stationary arm and a movable arm eachhaving a half rim journaled thereon to receive and support a tirethcrebetween, is releasably secured together at the end of a bridgebrace extending from the upper end of the stationary arm by a latch atthe upper end of said movable arm for presenting the tire tangently to abufiing drum; a preset gauging means for indicating the depth of cuttaken by said buffing drum into the tread rubber of said tire comprisinga scale supported on said bridge brace, a pointer movable along saidscale, a track on said stationary arm, a rider mounted in said track formovement therealong toward the axis of said tire, a tire engaging rollerextending from said rider for engaging the tread of said tire, a cableinterconnecting said pointer to said rider whereby said tire engagingroller is limited against movement toward the tread of said tire, andmeans on said scale for limiting movement of said pointer beyond apre-selected diameter reading.

3. Gauging means for a tire bufling machine in which a tire is supportedfor rotation on a horizontal spindle in a frame swingable horizontallyfor presenting the periphery of said tire to a buffing drum for removingtread rubber from said tire, said gauging means comprising a diameterscale supported on said frame, a pointer movably mounted on said scale,means operatively associated with said pointer for limiting movement ofthe latter relative to said scale at a pre-selected diameter readingtheron, a vertical guide on said frame, a rider arranged for up and downmovemnt on said guide, a tire engaging roller ex tending normal to saidrider above said tire for gravitational movement radially of saidspindle whereby said roller engages the periphery of said tire, cablemeans hav ing one end secured to said pointer and its opposite endanchored to said frame, pulley means on said frame above said guidefacilitating draping of said cable in the form of a U-shaped loopadjacent said rider, and a pulley journaled on said. rider and partiallycircumscribed by the loop of said cable for limiting gravitationalmovement of said rider and roller radially toward said spindle wherebysaid roller ceases to engage said tire after removal of tread rubbertherefrom beyond the diametric reading indicated by the pointer aspreset relative to said scale.

4. Gauging means for a tire bufiing machine in which a tire is supportedfor rotation on a horizontal spindle carried by a frame swingablehorizontally for presenting the periphery of said tire to a buffing drumfor removing tread rubber from said tire, said gauging means comprisinga scale supported on said frame calibrated to full scale diameterreadings, a pointer movably mounted on said scale, means operativelyassociated with said scale and pointer for limiting movement of thelatter toward zero reading on said. scale at any pro-selected diameterreading thereon comprising a vertical guide on said frame, a riderarranged for up and down movement on said guide, a gauge rollerextending perpendicularly from said rider above said tire forgravitational movement toward the periphery of the latter, cable meanshaving one end secured to said pointer and its opposite end anchored tosaid frame said cable having a U-shaped loop section draped adjacentsaid rider, and a pulley journaled on said rider supported in saidlooped section of said cable for limiting gravitational movement of saidroller radially toward said tire beyond the diametric reading indicatedby the pointer as limited by said means operatively associated with saidscale and said pointer.

5. In a tire buffing machine having a tire support articulatablehorizontally for presenting a tire tangently to a rotary bufiing drum; across bridge on said tire support above and parallel to the axis of atire supported on said tire support, a transverse scale across saidbridge, a guide track on said tire support adjacent and radially of atire thereon, a tire crown contour template roller for engaging theperiphery of the tire supported on said tire support, a rider arrangedfor up and down movement in said guide track and supporting saidtemplate roller for said engagement with the periphery of said tire, apointer movably adjustable along said scale, means for selectivelylimiting movement of said pointer beyond a desired position on saidscale, and a cable between said pointer and said rider for limitingmovement of said rider and roller radially toward said tire.

6. In a butfing machine including a tire support for presenting a tiretangently to a rotary buffing drum; a crown contour and diameter gaugingmeans comprising a guide track on said. tire support extending radiallyof a tire mounted thereon, a scale arm on said guide track extendingparallel to the axis of a tire on said tire support and overlying a tirethereon, a pointer movably adjustable along said scale arm, a riderarranged for movement in said guide track, a flexible connection betweensaid pointer and said rider for limiting movement of the latter towardthe axis of the tire on said tire support, a turret mount on said rider,and a plurality of template rollers for various tire widths mounted onsaid turret 12 mount and selectively movable into tire tread engagingposition relative thereto.

7. In a butfing machine including a tire support for presenting a tiretangently .to a rotary buffing drum; a crown contour and diametergauging means comprising a guide track on said tire support extendingradially of a tire mounted thereon, a scale arm on said guide trackextending parallel to the axis of a tire on said tire support andoverlying a tire thereon, a pointer movably adjustable along said scalearm, a rider arranged for movement in said guide track, a flexibleconnection between said pointer and said rider for limiting movement ofthe latter toward the axis of the tire on said tire support, a rollermount on said rider, and a tire crown engaging roller mounted on saidroller mount for engaging the tread of a tire on said tire support.

References Cited by the Examiner UNITED STATES PATENTS 2,007,507 7/1935Steiner 33172 2,636,277 4/1953 Hawkinson 33143 2,841,874 7/1958Richardson 33143 2,888,065 5/1959 Neilson 15713 ROBERT B. HULL, PrimaryExaminer.

SAMUEL S. MATTHEWS, Examiner.

1. IN A TIRE BUFFING MACHINE IN WHICH A TIRE IS SUPPORTED ON A POWERDRIVEN SPINDLE FOR ROTATING SUCH TIRE WHILE PRESENTING THE SAMETANGENTLY TO A ROTARY BUFFING DRUM FOR REMOVING TREAD RUBBER FROM SUCHTIRE; PRESET MEANS FOR INDICATING THE DEPTH OF CUT TAKEN INTO THE TREADRUBBER OF SAID TIRE DURING BUFFING THEREOF BY SAID BUFFING DRUMCOMPRISING A TIRE ENGAGING ROLLER ARRANGED FOR UP AND DOWN MOVEMENTRADIALLY FROM AND BY GRAVITATION TOWARD SAID SPINDLE WHEREBY SAID TIREENGAGING ROLLER RESTS UPON SAID TIRE FOR TURNING THEREBY DURING BUFFINGTHEREOF, AND MEANS FOR LIMITING MOVEMENT OF SAID TIRE ENGAGING ROLLER BYGRAVITATION BEYOND A PREDETERMINED RADIAL DISTANCE TOWARD SAID SPINDLEWHEREBY SAID TIRE ENGAGING ROLLER CEASES TO REST UPON SAID TIRE AND TOBE TURNED THEREBY FOR INDICATING VISUALLY THAT SAID TIRE HAS BEEN BUFFEDTO THE DESIRED DEPTH.